/*
* Based on arch/arm/include/asm/cacheflush.h
*
* Copyright (C) 1999-2002 Russell King.
* Copyright (C) 2012 ARM Ltd.
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License version 2 as
* published by the Free Software Foundation.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with this program. If not, see <http://www.gnu.org/licenses/>.
*/
#ifndef __ASM_CACHEFLUSH_H
#define __ASM_CACHEFLUSH_H

#include <linux/mm.h>

/*
* This flag is used to indicate that the page pointed to by a pte is clean
* and does not require cleaning before returning it to the user.
*/
#define PG_dcache_clean PG_arch_1

/*
* MM Cache Management
* ===================
*
* The arch/arm64/mm/cache.S implements these methods.
*
* Start addresses are inclusive and end addresses are exclusive; start
* addresses should be rounded down, end addresses up.
*
* See Documentation/cachetlb.txt for more information. Please note that
* the implementation assumes non-aliasing VIPT D-cache and (aliasing)
* VIPT or ASID-tagged VIVT I-cache.
*
* flush_cache_all()
*
* Unconditionally clean and invalidate the entire cache.
*
* flush_cache_mm(mm)
*
* Clean and invalidate all user space cache entries
* before a change of page tables.
*
* flush_icache_range(start, end)
*
* Ensure coherency between the I-cache and the D-cache in the
* region described by start, end.
* - start - virtual start address
* - end - virtual end address
*
* __flush_cache_user_range(start, end)
*
* Ensure coherency between the I-cache and the D-cache in the
* region described by start, end.
* - start - virtual start address
* - end - virtual end address
*
* __flush_dcache_area(kaddr, size)
*
* Ensure that the data held in page is written back.
* - kaddr - page address
* - size - region size
*/
extern void flush_cache_all(void);
extern void flush_cache_range(struct vm_area_struct *vma, unsigned long start, unsigned long end);
extern void flush_icache_range(unsigned long start, unsigned long end);
extern void __flush_dcache_area(void *addr, size_t len);
extern void __flush_cache_user_range(unsigned long start, unsigned long end);

static inline void flush_cache_mm(struct mm_struct *mm)
{
}

static inline void flush_cache_page(struct vm_area_struct *vma,
unsigned long user_addr, unsigned long pfn)
{
}

/*
* Copy user data from/to a page which is mapped into a different
* processes address space. Really, we want to allow our "user
* space" model to handle this.
*/
extern void copy_to_user_page(struct vm_area_struct *, struct page *,
unsigned long, void *, const void *, unsigned long);
#define copy_from_user_page(vma, page, vaddr, dst, src, len) \
do { \
memcpy(dst, src, len); \
} while (0)

#define flush_cache_dup_mm(mm) flush_cache_mm(mm)

/*
* flush_dcache_page is used when the kernel has written to the page
* cache page at virtual address page->virtual.
*
* If this page isn't mapped (ie, page_mapping == NULL), or it might
* have userspace mappings, then we _must_ always clean + invalidate
* the dcache entries associated with the kernel mapping.
*
* Otherwise we can defer the operation, and clean the cache when we are
* about to change to user space. This is the same method as used on SPARC64.
* See update_mmu_cache for the user space part.
*/
#define ARCH_IMPLEMENTS_FLUSH_DCACHE_PAGE 1
extern void flush_dcache_page(struct page *);

static inline void __flush_icache_all(void)
{
asm("ic ialluis");
dsb();
}

#define flush_dcache_mmap_lock(mapping) \
spin_lock_irq(&(mapping)->tree_lock)
#define flush_dcache_mmap_unlock(mapping) \
spin_unlock_irq(&(mapping)->tree_lock)

/*
* We don't appear to need to do anything here. In fact, if we did, we'd
* duplicate cache flushing elsewhere performed by flush_dcache_page().
*/
#define flush_icache_page(vma,page) do { } while (0)

/*
* flush_cache_vmap() is used when creating mappings (eg, via vmap,
* vmalloc, ioremap etc) in kernel space for pages. On non-VIPT
* caches, since the direct-mappings of these pages may contain cached
* data, we need to do a full cache flush to ensure that writebacks
* don't corrupt data placed into these pages via the new mappings.
*/
static inline void flush_cache_vmap(unsigned long start, unsigned long end)
{
/*
* set_pte_at() called from vmap_pte_range() does not
* have a DSB after cleaning the cache line.
*/
dsb();
}

static inline void flush_cache_vunmap(unsigned long start, unsigned long end)
{
}

#endif